Rick Santorum may be running an anemic third in Republican presidential primary polls in Florida, but his influence in Tuesday's crucial Sunshine State contest – and perhaps beyond – continues to outpace his survey numbers.

His performance during Thursday's GOP debate in Jacksonville provided perhaps the best view yet of the former Pennsylvania senator's increasing potential to play spoiler (see: Mitt Romney) or savior (see: Mitt Romney), and to take his unlikely quest for the White House deeper into the primary season than anyone every predicted.

Sure, the main event Thursday night was the spirited sparring between front-runners Newt Gingrich and Mitt Romney. With Gingrich often back on his heels explaining the difference between consulting and lobbying and defending a ka-jillion dollar moon settlement, a well-prepared Romney emerged on top, by points, if not a knockout.

But it was Santorum, the winner of the Iowa caucuses, who launched the most sustained debate attack of the season on Romney's role while governor of Massachusetts in implementing a state-based health care overhaul that requires residents who can afford it to have medical insurance. "We can't give this issue away," he said, and expect to take on President Obama over his health care overhaul and its individual mandate.

It was Santorum who kicked to the curb the other candidates' flat-tax fantasies, expressed sympathy for the "99 percent," and invoked what he characterized as a Reaganesque tax plan that would have a top rate of (cover your ears, Grover Norquist) 28 percent and a bottom rate of 10 percent.

And it was Santorum who most forcefully slammed as "not a responsible thing" Gingrich's grand plan rolled out Wednesday – Santorum called it a "grand scheme" — for a lunar colony of Americans who could achieve statehood if their numbers reached 13,000.

But, and this is a big but, Santorum also spent the early part of the debate neutralizing Gingrich's attack on Romney for allegedly wanting to kick out of the country illegal grandmothers as part of his "self-deportation" plan.

Romney denied that he wanted to kick out grandmas. "Our problem," he said, "is not 11 million grandmothers."

"I actually agree with Gov. Romney," Santorum said, about the self deportation and the all-important issue of illegal immigration. Which, sadly, didn't stop the grandma tit-for-tat between the muddied front-runners. But it did give Romney some breathing room.

Santorum also opened the door for Gingrich to engage in his favorite debate night exercise – attacking the media – by suggesting that Republicans might be better off focusing on issues rather than how much money Romney has amassed, or whether it was right or wrong for former House Speaker Gingrich to have signed lucrative contracts advising companies and interest groups. He didn't mention Freddie Mac.

Oh, Gingrich liked that, and turned to debate moderator Wolf Blitzer primed to pump up the anti-media machine. Unfortunately, Romney turned out to be a skunk at the bashing party, suggesting that "people" (a certain former speaker) who made accusations should be willing to defend them on the debate stage.

He posts up poorly against Obama, losing to the president by about 10 percentage points in a potential head-to-head matchup. But that's a sliver better than Gingrich would do against the president, according to poll averages on RealClearPolitics.com.

Democrats would welcome a Santorum surge. They are focused like a laser on Romney, who continues to run about even with the president in national head-to-head presidential preference polls. The barrage of debate-time emails sent out by the Democratic National Committee focused almost exclusively on criticizing Romney; Gingrich got a mention or two, but always linked to Romney.

So, what does Santorum want?

In Florida, he could potentially turn the race to Gingrich by dropping out and leaving his Christian conservative supporters looking for an alternative. That alternative won't be Romney, or Ron Paul, who is not campaigning in Florida. That makes Santorum's support from 10-plus percent of Florida Republicans look pretty important.

Santorum, however, is showing no sign of slowing yet. He doesn't have money, or organization, but he also doesn't have the hunted, haunted look of a candidate about ready to hang it up. Remember Texas Gov. Rick Perry's last days on the trail? Santorum has only gotten stronger on stage.

"The center point of my campaign is to be able to win the industrial heartland, get those Reagan Democrats back, talking about manufacturing, talking about building that ladder of success all the way down so people can climb all the way up," he said. "That's why I'm the best person to be able to go out and win the states that are necessary to win this presidency."

Polls, money and organization strongly suggest that's fantasy. But it's a fantasy that Santorum, and, no doubt Romney, would like to indulge for a bit longer. At least through Tuesday.

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